(n.) The act of extinguishing or making extinct; a putting an end to; the act of putting out or destroying light, fire, life, activity, influence, etc.
(n.) State of being extinguished or of ceasing to be; destruction; suppression; as, the extinction of life, of a family, of a quarrel, of claim.
Example Sentences:
(1) The stages of mourning involve cognitive learning of the reality of the loss; behaviours associated with mourning, such as searching, embody unlearning by extinction; finally, physiological concomitants of grief may influence unlearning by direct effects on neurotransmitters or neurohormones, such as cortisol, ACTH, or norepinephrine.
(2) The effect upon ethanol responding was found not to resemble a pattern of extinction, but rather was best described as a general overall reduction in responding.
(3) In a recent study, Orr and Lanzetta (1984) showed that the excitatory properties of fear facial expressions previously described (Lanzetta & Orr, 1981; Orr & Lanzetta, 1980) do not depend on associative mechanisms; even in the absence of reinforcement, fear faces intensify the emotional reaction to a previously conditioned stimulus and disrupt extinction of an acquired fear response.
(4) We conclude that the procedure used in this study is a non-intrusive intervention that is an extension of the current literature pertaining to sensory extinction.
(5) After 40 programmed minutes of acquisition and 12 min of maintenance, without notice, both schedules changed to extinction for 28 min.
(6) This differential absorbance is linear with increasing concentrations of Na2MoO4 and was used to calculate the molar extinction coefficient of molybdochelin at 425 nm (epsilon similar to 6,200).
(7) However, during massed testing, all subjects trained with response contingent CS termination showed an overall extinction influence, which was most pronounced in the medial subgroup, although the laterals showed frequency control as well.
(8) When reinforcement for competing behavior was withdrawn, however, rats resumed their original behavior and there were no overall savings in total responses to extinction.
(9) The relative amount of the crystals was measured in both amoeba strains on the basis of the integral extinction value.
(10) Chronic extinction of chain closed conditioned reflex in intact rabbits took five to six days.
(11) The amounts of phosphatidylcholine and sphingomyelin could be determined by high-performance liquid chromatography and ultraviolet absorption if the apparent extinction coefficient of the material analyzed was established.
(12) In a number of neurones the extinction of reflexes either does not change the reaction to acetylcholine, or enhances it.
(13) In Experiment 3, following an unsignaled reinforcement delay, groups receiving either no event or signaled food in the context responded faster in extinction than groups receiving no context exposure or unsignaled food.
(14) The optical extinction decreases as the red cell agglutinates grow, giving a parametric estimate of the haemagglutination rate.
(15) By calculating for DNA standard solutions the value of the ratio between the extinction at 665 nm after 15 min to the extinction of 600 nm after 2 min of the orcinol reaction it is possible to increase specifiaty of the orcinol method for determination of the RNA content.
(16) To lose the Sundarbans would be to move a step closer to the extinction of these majestic animals," said ZSL tiger expert Sarah Christie.
(17) Values obtained for thebuoyant density, isoelectric point, and extinction coefficient differed minimally; major differences were observed in the molecular weight and the characterisitc width of cylinders formed by in vitro-assembled T-layer of the wild-type and variant.
(18) The CS+ preference persisted for several weeks during extinction tests when both the CS+ and CS- were paired with IG water or with no infusions.
(19) The extinction coefficient at 550 nm for the oxidized enzyme is about 5300 (M subunit)-1 X cm-1.
(20) On this planet, extinction is the norm – of the 4 billion species ever thought to have evolved, 99% have become extinct.
Perpetuation
Definition:
(n.) The act of making perpetual, or of preserving from extinction through an endless existence, or for an indefinite period of time; continuance.
Example Sentences:
(1) If there is a will to use primary Care centres for effective preventive action in the population as a whole, motivation of the professionals involved and organisational changes will be necessary so as not to perpetuate the law of inverse care.
(2) We speculate that intestinal injury may also induce or perpetuate arthritis by systemic distribution of inflammatory mediators produced by intestinal immune effector cells.
(3) These findings suggest that community differences in levels of violence are perpetuated as Zapotec children learn community-appropriate patterns for expressing aggression and continue to express these patterns as adults.
(4) Post-labeling addition of 1 mM caffeine increased perpetuated blocks to a frequency of about 10% of the initial number of dimers in 4 h in XP16KO-II cells, but not in XP16KO-I and normal cells.
(5) This phenomenon may be of significance in the perpetuation of the disease.
(6) Trierweiler has broken a fundamental principle of French political life, an unwritten law inherited from the Ancien Régime and perpetuated by France's revolutionary nomenklatura, that the private life – and by that I mean sex life – of a public figure must remain inviolable.
(7) The ways in which medical personnel have opposed the political abuse of medicine is explored by a brief review of the opposition of Chilean doctors to torture, the involvement of South African doctors in opposing the abuse of health services in perpetuating apartheid, and the growing medical movement in opposition to nuclear war.
(8) Utilization data are known to be strongly influenced by the supply of facilities, particularly beds; unless this can be taken into account there is a likelihood that historical patterns will simply be perpetuated whether justified or not.
(9) Health care professionals hold attitudes toward persons with disabilities that are similar to those of society as a whole, and they may be actual perpetuators of this limiting practice.
(10) Moreover, genetics textbooks consistently employ confused or misleading definitions of the concept of heritability that, together with the reporting of discredited data, perpetuate a fundamentally inaccurate understanding of the genetics of intelligence.
(11) Even the most popular Shia cleric, Sayyed Mohammed Fadlallah , a man who has deeply affected the thinking of key Hezbollah leaders and cadres since the party's inception, now says in no uncertain terms that Shias and the country as a whole want to see, and should see, a strong Lebanese army as the nation's sole protector; and that the perpetually unstable confessional system must be ended as soon as possible.
(12) When this parliament votes for another referendum as it inevitably will, thanks to the perpetual crutch that the Greens provide, let’s not pretend it reflects the will of the Scottish people, because it doesn’t.
(13) The study has shown that: There is a significant increase in the severity of gingivitis during pregnancy; The gingival changes progressively increase during the course of pregnancy; The gingival changes are more marked than the periodontal changes seen during pregnancy (increase in periodontal disease was seen in only a limited number of cases); There was an appreciable increase in the calculus and debris deposits in the pregnant as compared to the nonpregnant women; Increase in the calculus and debris deposits was apparent in all the trimesters of pregnancy; Gingival changes showed a greater correlation with the calculus and the debris index in the pregnant than in the nonpregnant women; The role of the irritant oral deposits either as a precipitating or perpetuating factor in the genesis of gingivitis during pregnancy can not be excluded.
(14) Also in the Lords amongst the phalanx of red leather benches is a solitary seat curbed by an armrest provided for a perpetually drunken Lord (hence the saying?)
(15) In addition, TNF is produced and cleared from the blood-stream within a short period of time after an LPS stimulus, suggesting that TNF sets into motion a chain of events that may be self-perpetuating even in the absence of further TNF stimulus.
(16) One of the most tragic aspects of child abuse and neglect is that it is so often perpetuated from one generation to another.
(17) Yet, for many reasons, clinicians tend to resist rapid changes and perpetuate antiquated practices, diagnostic strategies, and clinical policies.
(18) The role of Ixodes ricinus and possible other vectors in perpetuating transmission of the European infection remains to be defined.
(19) It is caused by an intense, self-perpetuating process of clot-formation and lysis within the abnormal vascular channels of the haemangioma, and results in consumption of platelets and clotting factors.
(20) The central role of platelet-vessel wall interaction in the initiation and perpetuation of this process is well established.